Rear window defroster

My rear defrost just stopped working. Could it be a blown fuse. If so where do I start inside or under hood?

Do you have test light /and the know how to use one if so turn rear defrost on and check BATT 3 fuse in under hood fuse block is there battery voltage? If so go in the back seat there are two connectors on the rear window defrost grid test for battery voltage on connector with purple wire is there voltage? If not this Impala has a problem with a large white connector behind the right front kick panel that the purple wire melts and loses connection resulting in no power passing thru and on to rear defrost grid, check trhis and let me know.

The rear defogger on my wife's 2007 Chevy Impala will not work. I could not find a fuse so I replaced the relay and it still didn't work. I have a circuit through the back window but no power to the wires. The switch light does comes on when you press it. Please can you help. Its snowing here.

I am having the same issue. After reading another forum I looked at a wire harness under the front passenger kick board and found burnt wires. I spliced around the harness and still have no power to the defogger. It appears to me that GM has massively undersized the wiring to the defogger and I plan to run a jumper wire around all the harnesses straight from the fuse panel under the hood. It is a solid wire behind the harness at the kick panel. So I only plan to go that far. If you run your jumper from the relay controlling the defogger it should all work properly and only cost about $5 to fix.

P.S. The fuse that runs it is battery fuse 3 right next to the relay.